The invention relates to management of intelligent network services in a mobile communication network, particularly to management of supplementary subscriber services which include an intelligent network service. The invention also relates to the home location register of the mobile communication network.
The intelligent network IN can be used for offering a large number of different services to a subscriber in a data communication network, e.g. in a fixed network or mobile communication network. These services include a virtual private network VPN which enables use of short numbers between the subscribers in the local network, and a personal number where the intelligent network reroutes calls made to the personal number as defined by the subscriber. An example of such an intelligent network is described in Q-1200 series of ITU-T recommendations. Recommendations Q-1210 to Q-1219 define a set of features called CS-1 (Capability Set 1) and recommendations Q-1220 to Q-1229 define capability set CS-2. The invention and its background will be explained using the terms according to recommendation ETS 300 374-1 CoreINAP, but the invention is also applicable to intelligent networks implemented according to other intelligent network standards. In this application the term xe2x80x9cintelligent network recommendationxe2x80x9d means the abovementioned recommendation ETS 300 374-1. The relevant section of the recommendation is mainly the one defining intelligent network protocols.
The basic call state model BCSM defined in connection with the intelligent network describes different phases of call control and includes the points when call control can be interrupted to activate an intelligent network service. The BCSM recognizes the detection points in the call and connection process where the service logic entities of the intelligent network can interact with basic call and connection management features.
FIG. 1 illustrates structure of a prior art intelligent network. The intelligent network architecture comprises one or more service control functions SCF. The apparatus or network element which carries out the tasks assigned to the SCF is called a service control point SCP. In this application the SCF and the SCP are equal and, in the following, the name SCP is generally used. The SCP gives call setup instructions to the switching centre, or the switching centre may ask for call setup instructions from the SCP. If at some point of call setup it is noted, for example, that the subscriber B""s line is busy, the call can be routed to an alternative number. FIG. 1 also illustrates other intelligent network elements relevant to understanding the invention, such as call control function CCF, which comprises high-level call processing functions of the switching centre, such as establishment and release of transmission connections. A service data function SDF and a service data point SDP form a database which includes subscriber and/or service specific information. Specialised resource function SRF is an interface for the network mechanisms related to interaction with the subscriber. It may be related to intelligent peripherals IP which include more developed speech processing functions than the switching centres usually do.
Service switching function SSF is an interface between the call control function CCF and the service control function SCF. The network element performing the SSF function is called a service switching point SSP. An intelligent network service is produced so that the service switching point SSP asks for instructions from the service control point SCP by means of messages to be transmitted over the SSP/SCP interface when detection points related to the services are encountered. In intelligent network terminology these messages are called operations. In connection with an intelligent network service a service program is activated in the service control point SCP, and the function of the program determines the operations the SCP transmits to the SSP at each call stage.
FIG. 2 illustrates function of a prior art intelligent network at detection points. In step 2-1 the SSP transmits an lnitialDP operation (IDP) to the SCP, the operation including the information needed for call setup. This is followed by arming of detection points in the SSP. In step 2-2 the SCP sends a REQUESTREPORTBCSMEVENT operation to the SSP, which includes information on the instances of encountering detection points the SSP should report to the SCP. Next, in step 2-3, the SCP typically sends charging and/or interaction operations, such as FURNISHCHARGINGINFORMATION (save charging information related to the intelligent network service) or PLAYANNOUNCEMENT (give an announcement related to the intelligent network to the subscriber). In step 2-4 the SCP sends routing instructions to the SSP, such as COLLECTINFORMATION (collection of selection information from the subscriber), CONNECT (route the call to a new number), CONTINUE (continue call setup according to the same information) or RELEASECALL (release the connection). In intelligent network recommendations call setup is divided into certain rough phases called Point-In-Call (PIC). For example, it may be defined that in response to the COLLECTINFORMATIONOPERATION the SSP should continue call setup from phase PIC 2 and in response to the CONNECT operation it should continue call setup from phase PIC 3, etc.
In intelligent network architectures the defined detection points constitute the primary mechanism for reporting different events. The events of FIG. 2 described above are related to a detection point which is called a Trigger Detection Point (TDP). The SSP may make an initial inquiry to the SCP in connection with such a TDP detection point and receive information for call setup in it. Event Detection Points (EDP) represent the other type of detection points. Step 2-6 of FIG. 2 illustrates a moment when such an EDP detection point is encountered during call setup. The SSP reports that the detection point was encountered to the SCP, which in step 2-8 sends further call setup instructions to the SSP.
A problem related to prior art solutions utilizing the intelligent network in connection with a mobile communication network is e.g. that cooperation between the subscriber""s normal supplementary services and intelligent network services is poor. In practice this means that subscriber services do not function in all situations, e.g. it is typically impossible to register call forwarding by means of a short number because cooperation between the call forwarding service and the short number service is poor.
An object of the invention is to provide a method and an apparatus implementing the method to manage an intelligent network service substantially in the same way in the home network of a mobile station and in a visited network. The objects of the invention are achieved with a method and system which are characterized by what is disclosed in the independent claims. Preferred embodiments of the invention are disclosed in the dependent claims.
The invention is based on the idea that an intelligent network and a mobile communication network are combined utilizing the home location register of the mobile communication network. The home location register of the mobile communication network is supplemented so that it comprises the functionality of a service switching point, or at least the part of it essential for processing detection points. The home location register is armed with a subscriber-specific trigger point of intelligent network service which is related to supplementary service management procedures.
It is preferable to restrict the subscriber""s rights so that the subscriber may only manage supplementary services and the operator is responsible for management of basic services.
An advantage of the method and system of the invention is that the intelligent network and the mobile communication network can be combined flexibly, which means improved service management to the subscriber. This provides a clear competitive advantage for the operator. Since an intelligent network service is triggered in connection with the inquiry made to the home location register, the functionality of the invention is available regardless of whether the mobile station is within the area of its own network or another network. Even though the intelligent service trigger point included in the home location register is subscriber-specific, the calculated increase of memory need per subscriber is very small, approximately 10 to 20 bytes.